Director Paul Moran appeared at Trafford magistrates to represent Blackhouse Restaurants Ltd, which owns and operates the venue.

The firm, part of the Living Venture group which owns trendy Manchester city centre restaurants Australasia and Manchester House, admitted two health and safety offences, one relating to the welfare of an employee and another to a delivery man.

Prosecuting on behalf of Trafford council, David Goldstein said environmental health officers raised concerns as far back as 2007 about the open hatch, which covered a seven foot drop into the cellar. But the manager they spoke to left two weeks later after their visit and no action was taken.

On February 5 last year, the duty manager took a beer delivery and opened the hatch in the restaurant.

In a statement he said he shouted to colleagues to be careful but they later said they did not hear him.

He also placed a bin at the kitchen entrance to block it. At first, the manager stood guard over the open hatch but left to answer the phone. When Mr Lally walked through the kitchen he fell into the hole.

Half his body was in the hatch, and half stayed on the kitchen floor.

Mr Lally was off work for two weeks but continues to be employed at the restaurant, having been promoted to head chef. He is also taking civil action against his bosses, the court heard.

Delivery man Patrick Rowley also narrowly avoided the hole.

He said in a statement: “I had to step around the cellar hatch. I thought it was dangerous as there were no signs.”

Mr Goldstein said staff were aware of the dangers and used a bin to block the area and a staff member would normally stand guard.

After the accident, council officers reiterated safety rules like chains around the drop, only taking deliveries before opening and a better safety system and training, but this took some time to be fully implemented, he said.

He said an internal company letter obtained by the council showed blame had been placed on Mr Lally for not looking where he was going.

Rob Elvin, defending, said the firm accepted the safety process was not ‘an acceptable state of affairs’.

He added: “This has been and should be a wake-up call. They had a clean bill of health previously. The company has responded positively.”

Ordering the firm to pay a fine of £12,000 and costs of £6,000, chairman of the bench Simon Liddell said: “Although the actual harm was not too serious, the potential for serious harm did exist.”